As Dennis already answered, one way to do it is to use a space after:

    `\ `

Another, without the pesky space is to use the ["Fullwidth Reverse Solidus"][1]

    `＼`

Comparison:

    `\ ` versus
    `＼`

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On windows systems, you can often generate the full-width slash by holding down the <kbd>Alt</kbd> key and pressing <kbd>+</kbd> (numeric keypad), <kbd>F</kbd> <kbd>F</kbd> <kbd>3</kbd> <kbd>C</kbd> (lower-case is fine).

  [1]: http://www.fileformat.info/info/unicode/char/ff3c/index.htm